1. Field of the Invention
The present invention is generally related to railroad coupler mounts which secure equipment, such as end-of-train marker light and telemetry equipment, to the coupler head of the last car in a train and, more particularly, to railroad coupler mounts which secure equipment to the guard arm side of a coupler head.
2. Description of the Prior Art
End-of-train signalling and monitoring equipment is commonly used to meet modern railroad operating and safety requirements. Various train operating parameters (e.g., brake line pressure, and the like) are remotely monitored by the end-of-train equipment and telemetered to an engineer in the locomotive cab. In addition, the end-of-train equipment can include a marker light to identify the end of the train.
Over the years, several railroad coupler mount configurations have been devised for securing the end-of-train signalling and monitoring equipment to the coupler head of the last car in a train. U.S. Pat. Nos. 2,355,544 to McGowan and 4,487,060 to Pomeroy show signalling and monitoring equipment positioned inside the coupler head. Positioning the equipment within the coupler head is not ideal since it can be damaged by accidental mating with the coupler of another car, a situation which is likely in an active yard. Moreover, pusher locomotives cannot be connected without first removing the equipment. U.S. Pat. No. 4,592,217 to Fernandez et al. shows mounting the equipment on top of the coupler head by using a flag hole. This arrangement avoids accidental equipment damage; however, the arrangement has the disadvantage that not all coupler heads include a flag hole.
Most railroad couplers used in the United States and Canada are cast with four relief holes, or core holes, in the guard arm side of the coupler head. FIG. 1 shows a typical coupler head 10 used in the United States and Canada with four core holes 12a-b and 14a-b formed in the guard arm side. The core hole pairs, 12a-b and 14a-b respectively, are interconnected to provide passages underneath central region 16 and are divided from each other by a rib 18. The core holes 12a-b and 14a-b were not originally designed to serve any function on the finished coupler head 10; rather, they facilitated casting. Nevertheless, the industry has recognized that the coring holes are good locations for securing end-of-train signalling and monitoring equipment and several railroad coupler mounts have been devised which take advantage of them. For example, U.S. Pat. No. 4,520,662 to Schmid shows a coupler mount with four opposing jaw members which grip within the four coring holes 12a-b and 14a-b in the coupler head 10. The disadvantage of the Schmid device is that it is heavy and complicated and, therefore, difficult for a single person to install on the coupler head 10. U.S. Pat. No. 4,691,563 to Martin et al. and U.S. Pat. No. 4,876,885 to Martin et al. each describe railroad coupler mounts which include a banana shaped arm that extends through a core hole pair 12a-b or 14a-b, respectively. While the Martin et al. devices are easier to mount, there is still a need for alternative railroad coupler mounts which provide easy yet secure installation of the end-of-train signalling and monitoring equipment on the coupler head of the last car in the train.